Several processes are known in the art using either tertiary amine catalysts or diamine chain extenders. The following are among them.
U.S. Pat. No. 3,248,369 discloses a process for production of cross-linked resinous films utilizing a tertiary amine acrylate catalyst which is represented by the formula: ##STR1## wherein R and R.sub.1 are selected from the class consisting of alkyl radicals containing 1-4 carbon atoms and R.sub.2 is selected from the group consisting of hydrogen and methyl radical.
U.S. Pat. No. 3,630,987 discloses linear, segmented polyurethane elastomers and filaments therefrom, produced by reaction of NCO prepolymers with equivalent amounts of compounds of the formula: ##STR2## wherein A is m- or p-phenylene or ##STR3## as chain lengthening agents in polar organic solvents.
U.S. Pat. No. 3,794,621 discloses polyurethan elastomers and a method for preparing them wherein the polyurethane elastomers have the structural formulae: ##STR4## wherein R is an alkyl radical containing from about 1 to 20 carbon atoms which may be branched and which may contain heterto atoms if desired. The disclosed polyurethane elastomers are especially useful in the preparation of moldings which will be subjected to severe mechanical stress such as, for example, rollers.
U.S. Pat. No. 3,839,292 discloses a diamine curative system for polyurethane prepolymers having terminally reactive isocyanate groups comprising 2-cyano-p-phenylene diamine. The prepolymers are prepared by reacting a polymeric diol with a stoichiometric excess of 2,4-toluene diisocyanate, 2-6-toluene diisocyanate or an isomeric mixture containing predominantly the 2,4-isomer.
U.S. Pat. No. 4,026,840 discloses isocyanate reactions such as in their condensation with polyols to form polyurethanes and their polymerization to form polyisocyanurates. These reactions are promoted by certain hydroxyalkyl tertiary amine catalysts corresponding to the formula: ##STR5## wherein Y=CH.sub.3 or Z
Z=--CH.sub.2 CH.sub.2 OH PA0 n=1 or 2 PA0 R.sub.2, R.sub.3, =C.sub.1-4 alkyl or C.sub.2-6 alkoxyalkyl PA0 R.sub.4 =C.sub.3-9 alkyl and PA0 R.sub.5 =C.sub.1-4 alkyl
U.S. Pat. Nos. 4,039,514 and 4,054,556 disclose polyurethane/polyurea compositions comprising the reaction product of an organic diisocyanate, a glycol having a molecular weight of 500-5000 and a derivative of 2,4-diaminobenzoic acid selected from C.sub.1 -C.sub.8 alkyl and substituted alkyl esters, the amide, alkyl substituted amides, the anilide, substituted anilides, the nitrile and mixtures thereof.
U.S. Pat. No. 4,101,470 discloses compounds having the formula: ##STR6## wherein R is a lower alkyl, R.sub.1 is selected from the group consisting of hydrogen, alkyl, aryl, substituted aryl, alkaryl, substituted alkaryl, aralkyl, and substituted aralkyl. The patent also discloses a method of producing a polyurethane by utilizing the above compounds as catalysts in the reaction of an organic polyisocyanate with an organic polyester polyol or polyether polyol.
U.S. Pat. No. 4,133,943 discloses an improved process for the production of cellular or non-cellular polyurethane urea elastomers wherein diamines containing ester groups are used as chain lengthening agents. A characteristic feature of the process is the use of salts of aromatic diaminocarboxylic or sulphonic acids as a portion of the chain lengthening component.
U.S. Pat. No. 4,222,955 discloses a process for curing polyurethanes with substituted aromatic diamines. The diamines are individually selected from 3,5-diamino-4-tert-alkylbenzoates, 3,5-diamino-4-tert-alkylbenzonitriles and alkylene bis(3-amino-4-tert-alkylbenzoate).
U.S. Pat. No. 4,326,042 discloses the use of N-methoxypropylmorpholine, N-butylmorpholine and N,N'-dimethylpiperazine together as a catalyst system in an activator solution to give finer, more uniform cells to polyester-based polyurethane foams.
U.S. Pat. No. 4,350,778 discloses a method for making reaction injection molded polyurethane having improved paintability properties. The product is formed by reacting a high molecular weight polyhydric polyether, a low molecular weight active hydrogen-containing compound of at least dual functionality, a polyisocyanate and a catalyst combination comprising N-hydroxypropyl-N',N',N",N"-tetramethylimino- bispropylamine, dibutyltin dilaurate and an alkyltin mercaptide. This catalyst combination results in improved processing, a minimum of surface defects, excellent green strength and improved paintability using certain paints.
U.S. Pat. No. 4,482,690 discloses a process for the manufacture of polyurethane-urea elastomers formed by reacting the prepolymer of an organic polyisocyanate and a compound having at least two Zerewitenoff active hydrogen atoms with a chain extender comprising t-butylbenzenediamine. The utilization of t-butylbenzenediamine as an aromatic diamine chain extender imparts flexibility to the handling of reactable compositions due to the increase in pot life and imparts excellent tensile modulus to the resulting polymer.
U.S. Pat. No. 4,500,654 discloses a catalyst and process for producing polyurethanes by contacting an organic polyol and an organic isocyanate with a catalyst comprising an N-substituted alkoxyalkylpiperazine and preferably additionally comprising and N-alkoxymorpholine wherein the alkylene moieties of the morpholine and piperazine are independently selected from the group consisting of C.sub.1 to about C.sub.5 alkylene moieties and wherein the alkoxy moieties are independently selected from the group consisting of C.sub.1 to about C.sub.3 alkoxy moieties.